Rapid vehicle acceleration and fuel conservation are two mutually exclusive motor vehicle operating parameters. The steady increase in the cost of fuel has pushed the equation balance point toward fuel conservation in recent time. The desire to reasonably accelerate both passenger cars and trucks, however, has not disappeared. Those conversant with energy conservation acknowledge the most significant fuel consumption or waste occurs when the vehicle is braked to slow or stop it. The kinetic energy carried by the vehicle which arose by virtue of fuel consumption is dissipated and wasted as it is converted to heat in the brakes of the vehicle. This loss of energy and accompanying increase in fuel consumption has recently been acknowledged and addressed in that class of vehicles known as hybrid vehicles. In them, various regenerative systems attempt to recover the kinetic energy of the vehicle as it is braked by utilizing electric generators and storage batteries. The energy may then be used by an electric motor during subsequent vehicle accelerations.
Other energy storage systems exist. For example, a regenerative pump may pressurize hydraulic fluid which is stored in a reservoir; the stored hydraulic fluid and energy being utilized to drive a hydraulic motor during vehicle acceleration. Mechanically integrating such a system into a large vehicle such as a truck tractor involves many engineering challenges. The present invention is directed to such a system.